GB1587505A - Apparatus for controlling the current drain from an electric battery - Google Patents

Apparatus for controlling the current drain from an electric battery Download PDF

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Publication number
GB1587505A
GB1587505A GB15045/78A GB1504578A GB1587505A GB 1587505 A GB1587505 A GB 1587505A GB 15045/78 A GB15045/78 A GB 15045/78A GB 1504578 A GB1504578 A GB 1504578A GB 1587505 A GB1587505 A GB 1587505A
Authority
GB
United Kingdom
Prior art keywords
battery
current
voltage
operational amplifier
desired value
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB15045/78A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of GB1587505A publication Critical patent/GB1587505A/en
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0063—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with circuits adapted for supplying loads from the battery
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
    • B60L58/13—Maintaining the SoC within a determined range
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/24—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries for controlling the temperature of batteries
    • B60L58/25—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries for controlling the temperature of batteries by controlling the electric load
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/007—Regulation of charging or discharging current or voltage
    • H02J7/00712—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters
    • H02J7/00714—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters in response to battery charging or discharging current
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/007—Regulation of charging or discharging current or voltage
    • H02J7/00712—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters
    • H02J7/007182—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters in response to battery voltage
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/007—Regulation of charging or discharging current or voltage
    • H02J7/007188—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters
    • H02J7/007192—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters in response to temperature
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Secondary Cells (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)
  • Protection Of Static Devices (AREA)

Description

PATENT SPECIFICATION cii:
1) ( 21) Application No 15045/78 ( 22) Filed 17 April 1978 ( 31) Convention Application No 2726367 ( 32) Filed 10 June 1977 in r ( 33) Fed Rep of Germany (DE) oe ( 44) Completion Specification Published 8 April 1981
U ( 51) INT CL 3 H 02 J 7/00 ( 52) Index at Acceptance H 2 H BD ( 72) Inventors HELMUT HARER, ROLF SCHULZE, JOSEF JUHASZ ( 54) APPARATUS FOR CONTROLLING THE CURRENT DRAIN FROM AN ELECTRIC BATTERY ( 71) We, ROBERT BOSCH Gmb H, a German company of 50, Postfach, Stuttgart, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: -
The invention originates from an apparatus for controlling the current drain from an electric battery in accordance with the state of charge of the battery.
Apparatus is known for controlling the current drain from an electric battery, for example from a traction battery in an electric vehicle, in which the current maximum value is withdrawn as a protection against excessive discharge of the electric battery, on reaching an adjustable lower voltage limit As a lower voltage limit, for example, the final discharge voltage Ues, which amounts for example to 1 4 volts per cell during a half hour discharge current, is given by the battery manufacturer.
However, if this voltage is controlled so as to be held constant after reaching the final discharge voltage, without regard to the current which the battery can still deliver, an excessive discharge of the battery and with it irreversible damage to the battery results For example, due to an excessive discharge, the life of the battery, that is to say the number of possible discharge cycles, is substantially reduced.
One control apparatus for a d c machine is known from German OS 2 324 305, in which, by limiting the traction power during a highly charged condition over a wide discharge range of the battery, a maximum constant traction power is achieved For this purpose, the armature current desired value generator is formed as a variable resistor which is influenced by a voltage proportional to the armature voltage The output signal from the armature current desired value generator, which corresponds to the product of the armature current and the armature voltage and thus to the power, is transmitted through a limiter stage the cutoff point of which is provided by the charged condition of the battery The disadvantage in this apparatus is that, despite the improved use of the battery through constant power regulation results at a constant battery voltage.
According to the present invention there is 1 587505 provided an apparatus for controlling the current drain from an electric battery comprising a load connected to the battery and a current controlling unit connected in the load 55 current circuit and controlled by a desired value generator, circuit means are provided for sensing the battery terminal voltage and the battery current, together with means whereby the signals corresponding to the battery 60 terminal voltage and the battery current are added or multiplied together and the resultant signal is compared with a reference signal and the current controlled by the difference between the resultant and reference signals 65 Apparatus in accordance with the invention has the advantage of providing an undervoltage regulation dependent on current In so doing, during a low charge condition, the battery is regulated along a charging straight line If this 70 charging straight line is selected within a permissible range for the battery, for example %, there is a guarantee that the battery will not be damaged since the discharging procedure does not fall below the 10 % discharging straight 75 line at any instant.
Moreover, the apparatus in accordance with the invention is easy to construct and can use operating parameters (battery terminal voltage, battery current) which are ascertained anyhow 80 for traction control with, for example, an electric vehicle.
In a further preferred form of the invention, the current dependent undervoltage control is made additionally dependent on the temper 85 ature of the battery so that the very critical temperature conditions of traction batteries can also be taken into consideration.
A family of curves and a diagram illustrating the principle of one form of apparatus in 90 accordance with the invention are represented in the drawing and are described in more detail in the following description.
In the drawing, Figure 1 shows a family of discharging curves for a traction battery; Figure 95 2 is a diagram showing the principle of one embodiment of an apparatus in accordance with the invention for controlling the current drain.
The discharging family of curves for a 100 traction battery is illustrated in Figure 1 Moreover, the cell voltage Uz is plotted against the 1 587 505 cell short-circuit current lk in the usual manner.
Then discharging straight lines are given for the various charging conditions of the traction battery, for example, a first discharging straight line 1 for a fully charged battery ( 100 %), a second discharging straight line 2 for a half charged battery ( 50 %), a third discharging straight line 3 for a battery charged with the limit charge ( 10 %) and a fourth discharging straight line 4 for a discharged battery ( 0 %o').
The final discharge voltage Ues is inserted in the family of curves as a voltage straight line 5 The final discharge voltage UES is provided by the manufacturer for a particular type of battery and means that, for example, with a discharging current of 500 amperes, on reaching a cell voltage of 1 4 volts the final discharge voltage UES the charging limit condition of the battery is reached below which damage to the battery can occur.
A particular traction current le is necessary with an electric vehicle provided with traction batteries First of all, with a fully charged battery, a first working point 6 is set on the first discharging straight line 1 With increasing discharge, the cell voltage falls until a second working point 7 on the third discharging straight line 3 is reached With a control operation which is normal up till now, there is control from the second working point 7 towards a point 8 at a constant voltage, wherein, however, due to the under-voltage control at constant voltage, the fourth discharging straight line would be reached and an excess discharge of the battery would be effected thereby.
As is thoroughly described below, a current dependent undervoltage control is provided with the apparatus in accordance with the invention on reaching point 7, that is to say, it is not controlled to a constant voltage but to a combined value dependent upon the current and the voltage, for example the sum or product of the current and the voltage In this manner, it is possible to arrive from the second working point 7 along the third discharging straight line 3 at a working point 9 or even beyond.
In order to provide a current dependent undervoltage control, the battery terminal voltage Ub and the battery current lb must be measured and the two values be combined in such a manner as not to fall below a predetermined critical discharge line This can take place, for example, by summing a current and voltage signal and comparing it with a reference signal, a discharging straight line being electronically simulated thereby On the other hand, it is also possible to simulate a discharging straight line by an hyperbola which is produced by multiplication of the current signal with the voltage signal.
The circuit diagram showing the principal of an embodiment of the apparatus in accordance with the invention, is illustrated in Figure 2 A battery 10 supplies a motor 11 wherein a current regulating unit 12, which is in operative association with a desired value generator 13, is connected in the current circuit A first voltage converter 14 is connected to the terminals of 70 the battery 10 and a current sensor 15, which is connected to a second voltage converter 16, is arranged in the load current circuit The first voltage converter 14 and the second voltage converter 16 are connected to the inverting 75 input to an operational amplifier 19 through resistors 17, 18 Furthermore, the inverting input to the operational amplifier 19 is connected through a resistor 20 to a terminal 21 and through a resistor 22 to the output from 80 the operational amplifier 19 The non-inverting input to the operational amplifier 19 is connected to earth The output from the operational amplifier 19 is transmitted to a desired value limiting stage 23 which is connected 85 between the desired value generator 13 and the current controlling unit 12.
A signal corresponding to the battery terminal voltage Ub is formed in the first voltage converter 14 and is transmitted through 90 the resistor 18 to the inverting input to the operational amplifier 19 A signal corresponding to the battery current Ib is formed in the second voltage converter 16 and is transmitted through the resistor 17 likewise to the inverting 95 input to the operational amplifier 19 By applying a suitable voltage to the terminal 21, it can be established which corresponding discharging straight line in Figure 1 will be followed by the control with the apparatus 100 according to Figure 2 First of all, with a constant battery current Ib, the control does not then come into operation since the sum of the signals delivered by the voltage converters 14, 16 is greater than the signal originating at 105 the terminal 21 If, however, with an advancing discharge of the battery, the cell voltage falls and with it the battery terminal voltage Ub, then with the equality between the sum of the current and voltage signal and the reference 110 signal supplied through the terminal 21, control through the operational amplifier 19 begins, which produces engagement of the desired value limiting stage 23 which is connected between the desired value generator 13 and the 115 current controlling unit 12 Thus, by reaching a discharging straight line determined by applying a suitable reference signal to the terminal 21, control is at a constant sum of the current signal and the voltage signal which 120 corresponds to the control behaviour from the second working point 7 to the third working point 9 in Figure 1 In order to prevent too quick a re-control of the battery current Ib on reaching the preselected discharging straight 125 line, it is moreover possible, for example, by a suitable selection of the negative feedback applied to the operational amplifier 19, to provide a control characteristic in such a manner that the control starts with a dis 130 1 587 505 charging straight line which corresponds to the % charge condition and ceases with 5 % residual capacity.
In a further especially preferred embodiment of the invention, the actual calculation is effected so that the discharging straight lines of a battery are varied considerably with temperature In order to take into account the temperature influence when controlling the current drain, a temperature sensor 24 is provided which is located in thermal contact with the battery 10 The temperature sensor 24 is connected to a third voltage converter 25, which in its turn is connected through a resistor 26 to the inverting input to the operational amplifier 19 By means of this circuit, the starting point of the above described control is shifted in a suitable manner which can be determined by the third voltage converter 25, in accordance with the temperature of the battery measured by the temperature sensor 24.
In an alternative form of wach of the abovedescribed embodiments, the voltage and current-representative signals are applied to a device in which they are multiplied together and the resultant product signal is applied to the input of the amplifier 19.

Claims (3)

WHAT WE CLAIM IS:
1 An apparatus for controlling the current drain from an electric battery comprising a load connected to the battery and a current controlling unit connected in the load current circuit and controlled by a desired value generator, circuit means are provided for sensing the battery terminal voltage and the battery current, together with means whereby the signals corresponding to the battery terminal voltage and the battery current are added or multiplied together and the resultant signal is compared with a reference signal and the current controlling unit is arranged to be controlled by the difference between the resultant and reference signals.
2 Apparatus according to claim 1 characterized in that a first voltage converter is connected to the terminals of the battery and that a current converter is connected in the load current circuit, that the outputs from the first voltage converter and the current converter are applied through respective resistors to the inverting input of an operational amplifier which is also connected through a resistor to a terminal provided with the reference signal that the operational amplifier has negative feedback provided by a resistor and that its output is connected to a desired value limiting stage which is connected between the desired value generator and the current controlling unit.
3 Apparatus according to claim 2 characterised in that a temperature sensor is provided thermally connected to the battery and that a voltage corresponding to the battery temperature is transmitted to the inverting input to the operational amplifier.
A.A THORNTON & CO.
Chartered Patent Agents Northumberland House 303/305 High Holborn London, WC 1 V JLS.
Printed for Her Majesty's Stationery Office by MULTIPLEX techniques ltd, St Mary Cray, Kent 1981 Published at the Patent Office, 25 Southampton Buildings, London WC 2 l AY, from which copies may be obtained.
GB15045/78A 1977-06-10 1978-04-17 Apparatus for controlling the current drain from an electric battery Expired GB1587505A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2726367A DE2726367C2 (en) 1977-06-10 1977-06-10 Device for regulating the consumption of electricity from an electric battery

Publications (1)

Publication Number Publication Date
GB1587505A true GB1587505A (en) 1981-04-08

Family

ID=6011288

Family Applications (1)

Application Number Title Priority Date Filing Date
GB15045/78A Expired GB1587505A (en) 1977-06-10 1978-04-17 Apparatus for controlling the current drain from an electric battery

Country Status (7)

Country Link
US (1) US4210855A (en)
JP (1) JPS545537A (en)
DE (1) DE2726367C2 (en)
DK (1) DK153187C (en)
FR (1) FR2394126A1 (en)
GB (1) GB1587505A (en)
IT (1) IT1096519B (en)

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DE3031852C2 (en) * 1980-06-28 1983-11-10 Lucas Industries Ltd., Birmingham, West Midlands Method for determining the state of charge of an accumulator battery
JPS5747207A (en) * 1980-09-02 1982-03-18 Scovill Inc Machine for mounting valve to rim for tubeless tire
US4389608A (en) * 1981-09-30 1983-06-21 Dahl Ernest A Transformerless battery controlled battery charger
US4400661A (en) * 1981-10-02 1983-08-23 Ncr Corporation Voltage regulation and battery dissipation limiter circuit
US4394612A (en) * 1982-01-04 1983-07-19 Skil Corporation Battery charging circuit
US4423362A (en) * 1982-05-19 1983-12-27 General Electric Company Electric vehicle current regulating system
DE3435055A1 (en) * 1984-09-25 1986-04-03 Wabco Westinghouse Fahrzeugbremsen GmbH, 3000 Hannover DEVICE FOR PROTECTING AN BLOCKING PROTECTION ELECTRONICS AGAINST OVERVOLTAGE
JPH0666708B2 (en) * 1987-02-05 1994-08-24 日本電気株式会社 Speaker drive circuit
US4851743A (en) * 1987-10-27 1989-07-25 Eaton Corporation DC motor speed controller having protection
US5164653A (en) * 1990-10-26 1992-11-17 C & D Charter Power Systems, Inc. Battery discharge control system
BE1004817A3 (en) * 1991-05-16 1993-02-02 Vlasselaer Rudolf Van Security system for autonomous electrical energy sources, more specificallybatteries
SE500486C2 (en) * 1991-10-03 1994-07-04 Alfa Laval Agri Int Ways to adapt the operation of an electric fence to battery type
JPH05205781A (en) * 1992-01-28 1993-08-13 Sanyo Electric Co Ltd Over discharge prevention device for battery
JP3497521B2 (en) * 1992-02-13 2004-02-16 フオルクスワーゲン・アクチエンゲゼルシヤフト Method of controlling the voltage of an in-vehicle circuit of an automobile and an apparatus for implementing the method
US5410229A (en) * 1992-07-31 1995-04-25 Black & Decker Inc. Motor speed control circuit with electronic clutch
US5457365A (en) * 1992-12-04 1995-10-10 Integral Peripherals, Inc. Disk drive power management system
FR2706621B1 (en) * 1993-06-09 1995-08-04 Sagem Circuit controlling the electric current of a motor.
DE4403468C2 (en) * 1994-02-04 1998-07-09 Daimler Benz Ag Withdrawal current monitoring system for traction batteries in electric and hybrid vehicles
US5583413A (en) * 1994-09-06 1996-12-10 Cruising Equipment, Inc. Power conversion equipment monitor/controller method and apparatus
US5705913A (en) * 1995-01-31 1998-01-06 Mitsumi Electric Co., Ltd. Overdischarge detection device and overdischarge prevention device for a chargeable electric cell, operable with a variable threshold voltage to prohibit discharge in accordance with relative weight of a load
JPH101978A (en) * 1996-06-13 1998-01-06 Yutani Heavy Ind Ltd Battery-driven working machine
JPH10152865A (en) * 1996-11-22 1998-06-09 Yutani Heavy Ind Ltd Battery driven working machine
US20060204795A1 (en) * 2005-03-14 2006-09-14 Alfred E. Mann Foundation For Scientific Research Energy storage device charging system
US7530851B2 (en) * 2007-02-12 2009-05-12 Check Corporation Vehicle accessory control system
US7782018B2 (en) * 2007-09-10 2010-08-24 Maxim Integrated Products, Inc. Adaptive current limiting for any power source with output equivalent series resistance
JP2014143777A (en) * 2013-01-22 2014-08-07 Makita Corp Motor control circuit
DE102013204512A1 (en) * 2013-03-15 2014-09-18 Robert Bosch Gmbh Method and device for increasing the fuse when using battery modules
DE102013204534A1 (en) * 2013-03-15 2014-09-18 Robert Bosch Gmbh Battery cell device with short circuit safety function and method for monitoring a battery cell
CN109228907B (en) * 2018-07-16 2021-06-08 西安特锐德智能充电科技有限公司 Direct-current charging control method and high-power group charging system of electric automobile

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DE2321108B2 (en) * 1973-04-26 1976-06-16 Elektron Fabrik für physikalischtechnische Geräte Kerber & Co., 2800 Bremen DEVICE FOR MONITORING THE DISCHARGE STATE OF A BATTERY
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Also Published As

Publication number Publication date
JPS545537A (en) 1979-01-17
DE2726367C2 (en) 1984-12-13
DK258578A (en) 1978-12-11
FR2394126A1 (en) 1979-01-05
IT7824395A0 (en) 1978-06-09
IT1096519B (en) 1985-08-26
US4210855A (en) 1980-07-01
DK153187C (en) 1988-11-07
FR2394126B1 (en) 1983-02-25
DE2726367A1 (en) 1978-12-21
DK153187B (en) 1988-06-20

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19950417